1. Field of the Invention
The present invention generally relates to electrical connectors, and more particularly to an insulation displacement connector used to interconnect a variable number of electrical wires in a stacked arrangement and encapsulate the splice connection.
2. Description of the Prior Art
Insulation displacement connectors (also known as solderless electrical connectors) are known in the art, and are used to interconnect conductors which have an outer insulating layer. These devices typically include a central body or housing having one or more channels therein for receiving the conductors, and a U-shaped metallic contact element which provides the electrical connection between the conductors. As the U-element is lowered over the insulated conductor, the inner walls of the U-element penetrate the outer insulating layer (hence the term "insulation displacement"), and make contact with the central metal wire.
An early version of such an insulation displacement connector (IDC) is shown in U.S. Pat. No. 3,202,957 issued to E. Leach; that IDC has an M-shaped element, i.e., there are two parallel slots in the element for receiving the two wires to be interconnected. The prior art is replete with variations on this design, including alterations in the structure of the bodies and contact elements used in insulation displacement connectors. One of the most common designs uses a hollow body and a cap which is lowered into the body, the cap urging the metallic contact element over the wires. Another common design provides a cover attached to the hollow body by means of a "living" hinge. Both of these designs are illustrated in U.S. Pat. No. 4,954,098 issued to Hollingsworth et al.
Each of the prior art connectors, however, suffers from certain disadvantages. For example, while many of these connectors are designed for only one wire pair, others allow interconnection of a multiplicity of wires. Such multi-wire connectors provide a linear arrangement of entrances to the channels which receive the wires; in other words, the wires entering the IDC must all be generally parallel and coplanar. See, e.g., U.S. Pat. No. 4,435,034 issued to Aujla et al. This results in a flattened, elongated connector body which is often too bulky for applications where the size or shape of the connector is crucial.
Moreover, all insulation displacement connectors are designed for a specific number of wires, i.e., problems arise if the user wants to interconnect a smaller number of wires than the maximum number accommodated by the IDC. For example, if only five wires are attached to a six-wire IDC, one entrance will be left open, allowing ingress of water and other environmental contaminants which will degrade the connection. Although the connector may be filled with a sealant material, the sealant does not totally block such an unused entrance. Thus, prior art devices do not adequately address the need for variability in the number of wires which may be inserted into a given IDC.
Finally, most of the prior art IDC's provide wire entrances on only one side of the connector. Although this is acceptable for many applications, there are times when the interconnected wires must extend in opposite directions (an "in-line" configuration); when the oppositely directed wires exit from a common side, this creates an excessive strain in the wires near the IDC since each wire must bend about 90.degree.. It would, therefore, be desirable and advantageous to devise an insulation displacement connector for interconnecting multiple wires which is more compact than prior art connectors, and which may accommodate a variable number of wires. The connector should preferably be an "in-line" IDC, i.e., one which provides connection between two or more wires which are essentially parallel and collinear.